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<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <script>
        //基本数据类型
        //数值
           var age = 20;
           //字符串
           var name = "尚学堂";

           //布尔类型
           var learn = true;
           var flag =false;

           //引用数据类型，合成数据类型，复合数据类型，object对象
           var user={
            age:30,
            name:"iwen",
            humyin:false,
            jobs:{}
           }
          

           //都代表没有或者空 
           var hello=null;
           var world=undefined;
    </script>
 
</body>
</html>